river pollution

Hello
I have a 3rd kd bc that simulates a river. Which transport bc should I use to simulate a transfer of pollution from the river concentration to the aquifer ? If I use the mass transfer cauchy bc, should the in and out transfer rate be similar to the in and out transfer rate in the flow material properties panel ?

Thanks
Didier

Hi Didier

you should use a first kind B. C. for the contaminant concentration in the river water. Eventually you can put a constraint to avoid the mass tranfer from the aquifer towards the river.

Good luck

Gianmarco

Thanks gdidio
Actually we figured that out, by applying a in/out mass transfer rate, in addition to the in/out flow transfer rate that goes with the 3rd kd bc. This is necessary, unless the C that you specified in the river bc is also the C in the groundwater, which is usually not the case by several orders of magnitude. Fortunately we knew which mass had to be loaded from the river to the aquifer, so we could calibrate the in/out mass transfer rates.
Cheers !